It seems to be the question of the day: does Nokia 770 support USB? The official answer: yes it can, but it cannot supply enough power for the slaves.
However, take a look at this nifty hack, which enables Nokia 770 to act as a host and draw power for connected devices from a 9V battery. For about $2 worth of modifications Nokia 770 has been confirmed to run as a USB host.
Johan Hedberg on the developer list explained the inner workings of Nokia 770 Bluetooth module, since a lot of developers voiced concerns that having page scans and inquiry scans disabled for security reasons would make 770 a tough player in home PAN networks.
By default, the 770 will have both page scan and inquiry scan disabled (i.e. be non-connectable and non-discoverable). Enabling those scan modes is just a matter of issuing a simple HCI command. For example using the bluez-utils command line tools you can enable both scans the command “hciconfig hci0 piscan”. However, there will be no way to enable the scan modes from the default 770 UI.
Internet Tablet 2005 software edition is the basis for a range of new noncellular Internet tablet devices. The first device in the range is the Nokia 770 Internet Tablet.
The Nokia 770 Internet Tablet and all future devices powered by Internet Tablet 2005 software edition are designed primarily for consumers using a wireless local area network (WLAN) in the home or at public hot spots. A secondary function is to complement the capabilities of Nokia �s mobile phones as well as enterprise WLAN installations. The Nokia 770 Internet Tablet is a pocketable alternative to a PC, focusing on Web browsing and media functionality. It is targeted at home users who wish to browse the Internet or use various media via a WLAN or Bluetooth connection.